SteamyTea

Isolate each element, then calculate losses for each against the expected temperature ranges they experience. Pay special attention to windows and doors, corners and joints, and the often forgotten effects of air movement. Then remember that if all your insulation is open to external air, this can reduce the effective values. When you come to build, unless you are very conscientious, any hidden holes will loose energy. But as our chancellor said "not going to tell you where they are, but you have had 3 years knowing that they are there somewhere". Ok, not what he actually said, but you get the idea.

Yes, does not leave any headroom. Or the usual 30% oversizing to help increase efficiency.

In metric that will be 172 m2 In litres that will be, at 45p/litre, 2,667 litres In kWh that will be 28,000 kWh (10.5 kWh/litre) If your boiler works at 70% efficiency then you use a shade under 20,000 kWh a year If you deduct 3 kWh/day.person for hot water (going to assume there is 3 of you) then 3,300 kWh/year. This leaves ~16,700 kWh for space heating. Or ~100 kWh/m².year. Which seems high to me, but I have made some assumptions.

How about tapered threads. We laugh about the French not being able to agree on anything because they have over 360 different cheeses.

Isn't the idea to not get any air trapped because air is compressible. This can store more energy than the equivalent volume of liquid. It is why pressure vessels are tested with oil and not gas. If they do fail, then only a little oil comes out. We used to fit this sort of heaters to spa baths back in the 1980s. I can't remember one failing.

5 modules is probably around 1.5 kWp. This is not a very large system, so should not cost much, but as some have found, on a new build, it can cost less that tiling a roof. PV works when it is cloudy, solar thermal is the one that does not perform well in lower light levels. You can use PV to heat water.

Yes, I have just about done as much as I can, without buying a heat pump. More for record keeping now. Though I would like to measure the effects of sunlight on the house, but that could be as easy as just popping some sensors in the outside walls and under a couple of roof tiles.

One problem is that I do the anaylys in Excel/Calc. I am limited to just over 1 million lines of data. So I have to split the year into quarters(ish). Probably what I would do, not as if storing the data is the real problem. Can zip that up as it is all text files. At the moment I collect the data into daily files, then manually move them to the PC from the RPi, merge them together, open in Excel, copy it to the main Excel spreadsheet and then let it run though its averaging, mins and maxes, and do the charting. It is really my lack of programming knowledge that is the problem, and not wanting to have an over complicated system that could end up a bit flaky. What I have is very reliable, the ones I put in at Joe90's just chugs along collecting data, every few months or so I go and get the data off it.

Worth measuring it up, and seeing if you can find out what sort of cavity wall insulation there is. As you have new windows, it should be easy to work out the thermal losses though them. Do you know how much energy you use for heating at the moment?

I walked out of a shop after the sales assistance tried to not discount an item on sale. I even bothered to call up the head office, not as a complaint as such, more to point out the hopeless and confusing pricing policy. The person the phone actually agreed with me. Probably a temp.

What is the square metreage of the building. 5 Bedrooms says nothing. Is it detached, single or multi storey, exposed or sheltered, how much sun does it get. What age is the building and do you know the thermal properties of the building.

Is that regardless of the source? I use about 15 kWh/day for space heating, but only for about 100 days a year (though I am in a warm place). So that works out at 30 kWh/m2. So this seems quite achievable even with resistive electrical heating.

Have you a link to the silver active standards. To be honest, at first, I thought it was about pensioners building houses. We get silver surfers down here, they have the poshest campervan.

I may play around with the sample rate and see where it becomes unacceptable. Anything over half a kWh a day is probably too much as in the summer I sometimes only use 3 or 4 kWh a day.

Find out where the testing stuff is at the moment, see if it is close by.

I use a CurrentCost ENVI to collect my electrical energy usage. This samples every time there is a 1 Wh pulse on the meter LED. It seems pretty reliable and not far out what my meter readings are. The trouble is, there is a lot of data as it take a reading every 6 to 8 seconds. So a typical day can have 11000 plus readings. This is quite a strain on processing power when I come analyse it. So for a laugh, I wondered how much accuracy I would loose if I just looked at 1 in 6 of the readings. As I suspected, very little. There was, at the 0.1°C resolution, no difference in the temperature data. And no more that 8 W out on the power consumption. To be honest, I can live with that as, at worse, it is only 0.2 kWh/day out, that that is lost in normal variation. So I may rewrite the code I cobbled together to randomly sample 1 in 6 readings (about 1 a minute). This should still pick up loads like a kettle.

Got to put into perspective: Greenhouse gas Mauna Loa sulfur hexafluoride timeseries. According to the Intergovernmental Panel on Climate Change, SF 6 is the most potent greenhouse gas that it has evaluated, with a global warming potential of 23,900[28] times that of CO 2 when compared over a 100-year period. Sulfur hexafluoride is inert in the troposphere and stratosphere and is extremely long-lived, with an estimated atmospheric lifetime of 800–3,200 years.[29] Measurements of SF6 show that its global average mixing ratio has increased by about 0.2 parts per trillion per year to over 9 ppt as of February 2018.[30][31] Average global SF6 concentrations increased by about seven percent per year during the 1980s and 1990s, mostly as the result of its use in the magnesium production industry, and by electrical utilities and electronics manufacturers. Given the small amounts of SF6 released compared to carbon dioxide, its overall contribution to global warming is estimated to be less than 0.2 percent.[32] In Europe, SF 6 falls under the F-Gas directive which ban or control its use for several applications. Since 1 January 2006, SF 6 is banned as a tracer gas and in all applications except high-voltage switchgear.[33] It was reported in 2013 that a three-year effort by the United States Department of Energy to identify and fix leaks at its laboratories in the United States such as the Princeton Plasma Physics Laboratory, where the gas is used as a high voltage insulator, had been productive, cutting annual leaks by 16,000 kilograms (35,000 pounds). This was done by comparing purchases with inventory, assuming the difference was leaked, then locating and fixing the leaks.[7]

I live next to the third most polluted road in the UK, I think this is down to there being limited mains gas available, so heating is still done with coal and timber.

Let us know when, I have the first 3 days of the week free at the moment.

Have you cured the air leak on the inlet pipe yet?

Yes, as I do. But we are very restricted as to where we can smoke them.

Not how it works, it is an accumulation. Trouble is, like a lot of risks, people need constant reminding. Why we have road signs and health warnings alcohol.

Gets even worse when you compare different sized buildings. Even if you forget about the price of the land, building a small house, compared to a medium sized one, will be more expensive per square meter because of the fixed costs i.e. you cannot have half a sewer, half a kitchen or bathroom.

Seems odd with the known health hazards (of both). Do you allow smoking in your holiday lets?

Evan a small woodburner is hazardous to health. Taking a bit of a risk in my opinion.